Question

A random sample of n=25 individuals is selected from a population with μ=20 , and a treatment is administered to each individual in the sample. After treatment, the sample mean is found to be M= 22.2 with SS= 384.
a. How much difference is there between the mean for the treated sample and the mean for the original population? (Note: In a hypothesis test, this value forms the numerator of the r statistic.)

b. If there is no treatment effect, how much difference is expected between the sample mean and its population mean? That is, find the standard error for M. (Note: In a hypothesis test, this value is the denominator of the t statistic.)

c. Based on the sample data, does the treatment have a significant effect? Use a two-tailed test with α= 0.05.

Answer 1

Answer:

a) how much difference in number of mean is 2.2

b) standard error of sample mean = 0.8

c) the test statstistical value is greater than the critical value ,hence we reject the null hypothesis. we can conclude that the treatment thus have a significant effect

Step-by-step explanation: